I don't remember any 50s on the "safe" route in. They weren't really a threat.
Other players and getting flagged? Well, the bonus series *is* one of the big crossover points between the two factions (and was even more when it came before Tat). But you can pop safely into the instance quickly after beating the not-very-tough ramp guards, and if you're trying to *drive* your way out afterwards instead of QTing... why are you doing that!?
I play on a pvp server so getting flagged is zero problem. But those on pve servers will get flagged and potentially be attacked attempting to do this mission. I've seen lots of complaints about forced pvp and on a pve server I believe they are valid. Again, I play on pvp server so expect nothing less.
The main point was heroics are usually tougher than the route to get to them. I'm lvl 39 and every heroics was a climax of difficulty. Lab Animals, either direction is what you would call anti-climatic. Maybe it's designed that way to change things up. *shrug*
Also, as a minor point, the green map markers point you to the toughest way...directly to a lvl 50 droid that's unavoidable. You should go check the alternate route again. I just did. There are level 50 droids anyway you attempt to go in this heroic. One route through the network security district can be carefully walked around but the other can not.
And no one said anything about driving out. I quick traveled. I'll be damned if I'm going to incur more repair charges than I had before I got in the actual heroic.